The Kremlin warned the U.S. about Boston bombing suspect Tamerlan Tsarnaev in 2011—but they held back some crucial information according to a new report in The Wall Street Journai. U.S. officials tell the paper that Russia neglected to mention several text messages sent by Tsarnaev's mother to a relative in Russia suggesting that Tamerlan was interested in joining militant groups. Such specific information could have spurred a more in-depth investigation on the FBI's part. Of course, the paper notes, incomplete data-sharing goes both ways. Can't we just get along?